A Novel Topology for MPPT and Voltage Control in a Solar-PV-based DC Microgrid under Partial Shading Conditions

This paper presents a novel topology for Maximum Power Point Tracking (MPPT) and voltage control in a solar PV-based DC microgrid, specifically designed to operate efficiently under Partial Shading Conditions (PSCs). PSCs introduce multiple peaks in the power-voltage (P-V) curve, leading to inefficient energy extraction. To overcome this, a Hybrid Gradient Estimation-Voltage Reference Shifting (HGE-VRS) algorithm is developed. The algorithm combines slope-based MPPT with adaptive voltage reference sweeping to accurately detect the Global Maximum Power Point (GMPP) under shading patterns. Additionally, a decentralized voltage control mechanism ensures stable DC bus operation under fluctuating load and generation. The proposed method eliminates the need for complex reconfiguration and reduces power oscillations near the MPP. Simulation and experimental validations using hardware emulators confirm improved convergence speed (0.12 s), tracking accuracy, and power stability compared to conventional MPPT techniques. The system demonstrates effective power sharing between the PV array and battery energy storage, ensuring reliable supply during dynamic irradiance and load conditions. The proposed topology significantly enhances energy utilization, reduces losses, and stabilizes voltage, making it suitable for real-world microgrid applications with high solar penetration.